Tape Emulation Alternate Data Path

1. A method of emulating tape data, comprising: providing a first storage device coupled to a host by a first link; providing a tape emulation unit coupled to the host by a second link, the tape emulation unit including a data mover; providing a third link between the first storage device and the tape emulation unit; transferring data from the host to the first storage device using the first link; transferring data from the host to the tape emulation unit using the second link; and in response to a command to transfer data between the first storage device and the tape emulation unit, transferring data between the first storage device and the data mover using the third link while maintaining the first link and the second link, wherein data that is transferred bypasses the host.

2. A method, according to claim 1 , wherein the tape emulation unit includes a front end component coupled to the host and a second storage device, the data mover being interposed between the second storage device and the front end component.

3. A method, according to claim 2 , wherein the front end component is coupled to the data mover using a GigE switch.

4. A method, according to claim 2 , wherein the data mover uses NFS to access data.

5. A method, according to claim 1 , wherein at least one of the first and second data storage devices are data storage arrays.

6. A method, according to claim 1 , further comprising: monitoring a state of a transfer to determine when the transfer is complete.

7. A non-transitory computer-readable medium containing software that that emulates tape data, the software comprising: executable code that causes data to be transferred from a host to a first storage device via a first link between the host and the first storage device; executable code that causes data to be transferred from the host to a tape emulation unit via a second link between the host and the tape emulation unit; executable code that receives a data transfer command from the host, wherein the transfer command directs data to be transferred between the tape emulation unit coupled to the host and the first data storage device via a third link between the first storage device and the tape emulation unit; and executable code that transfers data between the first storage device and a data mover that is part of the tape emulation unit using the third link while maintaining the first link and the second link, wherein data that is transferred bypasses the host.

8. A non-transitory computer-readable medium, according to claim 7 , wherein the tape emulation unit includes a front end component coupled to the host and a second storage device, the data mover being interposed between the second storage device and the front end component.

9. A non-transitory computer-readable medium, according to claim 8 , wherein the front end component is coupled to the data mover using a GigE switch.

10. A non-transitory computer-readable medium, according to claim 8 , wherein the data mover uses NFS to access data.

11. A non-transitory computer-readable medium, according to claim 8 , wherein at least one of the first and second data storage devices are data storage arrays.

12. A non-transitory computer-readable medium, according to claim 8 , further comprising: executable code that monitors a state of a transfer to determine when the transfer is complete.

13. A tape emulation unit, comprising: a front end component; a data mover coupled to the front end component; and a first storage device coupled to the data mover, wherein in response to a command to transfer data between a second storage device coupled to a host via a first link and the tape emulation unit which is coupled to the host by a second link, data is transferred between the data mover and the second storage device using a third link while maintaining the first link and the second link and wherein data that is transferred bypasses the host and wherein data is transferred from the host to the second storage device using the first link and from the host to the tape emulation unit using the second link.

14. A tape emulation unit, according to claim 13 , wherein the front end component is coupled to the data mover using a GigE switch.

15. A tape emulation unit, according to claim 13 , wherein the data mover uses NFS to access data.

16. A tape emulation unit, according to claim 13 , wherein at least one of the first and second data storage devices are data storage arrays.

17. A tape emulation unit, according to claim 13 , further comprising: a host bus access unit coupled to the data mover and used to transfer data therebetween.